Posted
by
timothy
on Thursday June 20, 2013 @11:54AM
from the and-they're-delicious dept.

MTorrice writes "Crab shells usually are just a nuisance that you have to crack and dig through to get the delicious meat inside. But one team of materials scientists thinks the shells could help them fabricate materials for long lasting batteries. The team used the nanostructures (abstract) found in the crustacean shells as templates to make sulfur and silicon electrode materials for lithium-ion batteries. Sulfur or silicon electrodes have a 10-times greater theoretical energy storage capacity than electrodes used in commercial batteries."

So if I understand this correctly, by increasing the surface area of the electrodes, you increase storage density. We already knew that. The problem is those electrodes corrode over time... ions swap between the two plates, which is why we don't go through the effort of manufacturing them with lots of little pits and twists in them, because they'll just corrode that much faster. No pure metal can resist this, and alloys that can generally make poor foundations to build batteries on. Plus there's manufacturing cost. For something like a car battery... that's important. For something like a cell phone, I can see some merit in making batteries with a higher energy density at the tradeoff of shorter life. Of course, they're already pretty short right now...and expensive.:(

Dividing both by 1000 gives 1.23 Ah/g and 3.06 Ah/g respectively then multiply by the voltage to get Wh/g. So if you have ~11 volts, you get the density of gas for sulfur, and ~5 volts gives you better than gas for silicon.